I'd view a house differently if the homeowner was present and always prefer them not to be there if possible.
It's kind of a big decision so you should do what ever the buyer wants imo.
Why would you view it differently if the buyer was present, it's still the same bricks and mortar? I really don't agree you should do what ever the buyer wants either as the process is never as simple as view, offer, accept, exchange there is always negotiation these days and you don't want to appear to be a walkover!
We are in the lucky position that if we sold our house there would a be a queue of people down the street and half a dozen offers of asking price or more on the first weekend, it's how the market in the area works so we wouldn't have to entertain slightly odd buyer requests for us to not be in our own home as plenty of other people would be happy to buy anyway!