I've stayed at a few RI's with a small dog and noticed the rooms to be ok and relatively, pet hair free. I know Starwood properties don't usually charge an additional fee when I have a pet (those that allow them), but their rooms aren't generally as clean as the RIs I've been at.

On a personal note, I don't mind a modest charge for extra cleaning because of people's allergies...as long as it's done. But I've wondered whether $75-100 is a bit excessive.