Yes, two reasons:

Butterfly Effect: You go to a tavern to eat, you take a seat which was free later on in the original timeline, so somebody who in the original timeline was at your seat takes seat somewhere else, which makes him not overhearing some conversation he did overheard originally, or overheard some other he did not in the original, thus potentially changing his perceptions and decitions, which will have an influence on others and so on. Mind, not everytime you have lunch you change fate, it is just the accumulation of minimal probabilities everytime you are there where nobody was at originally.

Your very presence might change decitions on the spot: You want to observe interesting events in the past, but those many times are stressful moments for everyone involved, how would their decition making be influenced by somebody unknown staring at them ? Extreme example, say you decide to observe one of the Ripper's killings to learn his identity and he spots you, he might well flee, or go for you giving the victim a chance to flee. Less extreme, you decide to witness Christ's cruxifixion. How will the Centurion leading the guard react to another body in the crowd ? Maybe he will not notice at all, maybe it will be enough to make him nervous about the amount of people gathered and change his decitions. How will the very crowd react to you? It is expecting for everyone to shout insults and start a row directed at you if you do not join, thus making the centurion even more nervous? Or the other way around, it is all friends and they expect everyone there to be lamenting the event, and you're only there staring like a statue. Again, your mere presence does not warrantee fate is changed, but it is something taken into account by others when deciding what to do, and might be enough to decdie for a subtly different line of action. Or an extremely different one if the Centurion gets angry enough to charge down the hill pilum-first to dissolve the row you caused.

Yes, two reasons:

Butterfly Effect: You go to a tavern to eat, you take a seat which was free later on in the original timeline, so somebody who in the original timeline was at your seat takes seat somewhere else, which makes him not overhear some conversation he overheard originally, or overhear some other he did not in the original, thus potentially changing his perceptions and decisions, which will have an influence on others and so on. Mind, not every time you have lunch you change fate, it is just the accumulation of minimal probabilities every time you are there where nobody was at originally.

Your very presence might change decisions on the spot: You want to observe interesting events in the past, but those many times are stressful moments for everyone involved, how would their decision making be influenced by somebody unknown staring at them ? Extreme example, say you decide to observe one of the Ripper's killings to learn his identity and he spots you, he might well flee, or go for you giving the victim a chance to flee. Less extreme, you decide to witness Christ's crucifixion. How will the Centurion leading the guard react to another body in the crowd ? Maybe he will not notice at all, maybe it will be enough to make him nervous about the amount of people gathered and change his decisions. How will the very crowd react to you? It is expecting for everyone to shout insults and start a row directed at you if you do not join, thus making the centurion even more nervous? Or the other way around, it is all friends and they expect everyone there to be lamenting the event, and you're only there staring like a statue. Again, your mere presence does not guarantee fate is changed, but it is something taken into account by others when deciding what to do, and might be enough to decide for a subtly different line of action. Or an extremely different one if the Centurion gets angry enough to charge down the hill pilum-first to dissolve the row you caused.