Don't worry about it. I am a deerhunter and it does not bother me when someone walks by. You did no harm if the fellow stayed put he may have gotten a crack at the a deer you stirred up.

Dont let it bother you. like they said it could have helped him out. It happens.

I got really frustrated my first time on public land just that way; it seemed I could not find a place where I wasn't 50 yards from somebody. I felt like a real jerk.
But like charlie elk and Skeep say, your movement can benefit them, as deer that move to avoid or keep tabs on you may become visible to the guy in the stand. Most of my deer have been taken as a result of some other guy bumping them.
Seems like a compliment to his choice of a stand that you didn't see it in time to avoid him, either.

yeah i walked into a guys shooting lane and it felt like a seeing it threw the eyes of a deer just scanning up the tree and seeing a guy in a gillie suit. i said sorry and got out of the area the same way i came in. i really felt bad. during gun season on public land that really gets the deer moving i like to plan my spots by the hunter pressure in some places and sit longer than them as many leave at noon and then come back making a period of unnatural deer movement that often ends in me seeing them.

yeah its all been said dont worry about it. you probably pushed some deer to him and if not you just stirred up some action

Most all of have had this happen to us. What to do? find and get to your stand a little deeper into the woods than the rest of the hunters and at least 1 hour sooner than you would normaly go, letting all the other hunters push deer to you. Become the see'er not the pusher!!!!

Exactly what you did. Don't beat yourself up about it. Things happen. You weren't trying to cause him problems.