I don't own calipers but I have access to some (I think/hope).

I went to another local bike store and the guy there was in a rush and didn't seem to want to talk to me but he said it's normal for single speeds and fixed gears, also he said I could lube my chain more and ease the tension on my chain but it might slip off if I hit a bump? He also said my chain doesn't need to be any looser.

Is this issue a severe? Should i be worried my components will be wearing down exponentially with each ride?