Have taken by bike into hotels in multiple countries. I never ask, I just take it in with me. I have only had one hotel outright refuse, that was the Intercity Hotel in Enschede. Eventually they put the bike in a cleaners store cupboard, which was acceptable. The Best Western in Rastatt weren't happy, and tried to argue with me, pointing me to a wheel bender rack out front. I stood my ground and eventually they let me in. Ibis near Zurich looked at the mud on my bike and tried to say no "That? That's been there for 500km!" and they let me in. The Ibis in central Köln asked me to put it in the secure underground carpark, which given it was accessible only to guests, and had cctv etc... I was ok with, we had a negotiation about it before I agreed to this. Hotel in central Belgrade said "you can't take your bike in your room" "I don't have a lock" "Oh, it's not that you aren't allowed, it's just there's no lift, and you're on the 1st floor" "Not a problem" *shoulders bike and walks up stairs*. Look on her face was rather good.
IMHO, if you ask, they have to think about it. If you just do it, then it's a reaction. Generally the posher the hotel, the more likely they are to not give a damn.
J