McDonalds has a clear policy regarding use of its drive-thru facilities. That page was last updated in March 2011, and it runs as follows (appalling grammar in the question left uncorrected):
What are the policies for service in the drive thru lanes?
Q: i have a serious question for you what is the polices for your drive thru i was refused service because i came thru on a bicycle in the drive thru and there is nothing stating that bicycle are allowed and will be refused service i would like to know why that is because i am seriously offended
A: Thanks for your question. McDonald’s drive thru is for people in motor vehicles only, bicycles are not permitted on our drive thru due to the health and safety policies we have in place.
Now, I mentioned a few weeks ago how some idiot attempted to go through one on horseback. She was so deranged that she forced her daughter to drag 
her horse into the restaurant, whereupon it crapped on the floor – probably as a result of being frightened – while people were eating. Well, this story tells how some idiot on a bicycle tried the same trick and was similarly refused service.
Of course, being in The Mail, it is obviously McDonalds who are in the wrong.
The idiot in question this time was one of those clowns who rides around with a baby-buggy trailer on his bike. In this particular case, he had his 4-year old son in the damned thing. I wonder what publicity he’d now be seeking if he’d have been hit by a motorist who didn’t see the bloody thing sticking out behind?
The funny thing is that the prat waited in the queue of cars for 15 minutes before reaching the window. He’d have gotten served in less than five minutes if he’d have simply gone inside. He displays the sort of logic common to cyclists:
I was baffled. If my bike is safe enough for the road, surely it is safe enough for a drive-thru in a car park with a 5mph limit? It’s a daft policy.
I’ll wager that it doesn’t take much to baffle him under normal circumstances if he finds this one confusing.
The Mail has got plenty of pictures of him at the drive-thru – all set up for the occasion, of course. And they quote a Health & Safety Executive (HSE) spokesman:
[he] said there was no legislation preventing cyclists from using a drive-thru.‘McDonald’s should state the real reason for turning away cyclists rather than using health and safety as a catch-all…”
McDonalds has not said that there WAS legislation, nor have they used it as a “catch-all”. They make it clear that it is THEIR policy on health & safety grounds. See the difference? You have “Health & Safety” with capitals, and “health & safety” in lower case – one is a pile of idiotic bureaucracy, and the other an attempt to apply common sense whilst still being bound by idiotic rules from the other. See if you can work out which one’s which. I also wonder if that HSE clown would have argued the same about the silly cow on the horse?
And in any case, if a cyclist WAS to be injured at a drive-thru, the HSE would be all over McDonalds like a rash. And by that, I mean a sudden and really nasty rash – not the lingering, long-term rash that the HSE is to businesses the rest of the time.
It appears that McDonalds has got a real problem with people of restricted intelligence trying to use the drive-thrus. The Mail’s story mentions how last month it turned away a 76-year old on a mobility scooter from a branch. McDonald’s apparently apologised – but they shouldn’t have.