I don't think I would pay a fee for simply trying on something in a store. That is part of the justification for paying a little more at a physical store than online.
I have no qualms about buying online when the pricing or selection difference is big, but people who go into a store expecting workers to expend time and effort helping them find the right product in the right size while fully intending to take that information with them to buy cheaper online are scum (imho).