to be annoyed that we were going to be charged for extra butter?

[NotEnoughTime]

I went out for lunch on Sunday with my DH (a very rare occurence). We went to a restaurant that we have been going to for years. We go there on special occasions ie birthdays, anniversaries etc. It usually costs around £60-70 for lunch for two with no alcoholic drinks.

Anyway, we ordered soup for our started and we were given bread with this. We used the (small amount of) butter and then asked for some more butter. We were then told we could have some more butter but we would be charged a £1 for it! I thought this was very strange. Has anyone else ever been charged extra for butter? The waitress insisted this was common practise but I have never come across it before. I know it was only a £1 but I thought it was very mean.

Working most of my life in catering I think it's preposterous to charge for butter. Those small individually wrapped packets are between 10p-14p each from catering suppliers. A serving in a ramekin from a large block is even cheaper.
I perhaps wouldn't have not tipped (unless the tips were taken by the boss like in one restaurant I worked in - thieving bastard used to make a good £100-£200 in tips a night when it was me doing all the waiting on while he sat drinking wine or wasn't even there) but I would have complained on my way out to a manager and gone to town on all the review sites I could.