Restaurant booking rudeness?

[Dave]

I wanted to book a table at a local restaurant in Dublin for my birthday. I follow them on Twitter and they have an offer on for followers -

Tweet us with date,time (12,2,4,6,8pm),no of ppl (max4) including #tweetseats in ur request & u eat for free if slot is available. 24hrs notice needed

I did just this, twice, before the 24 hr period but got no reply. I then tweeted that I was disappointed they didn't get back to me, and they replied with - "Get your s**t together and request in time."

Is it just me or is that rather rude? Especially on a public forum like Twitter...
I have since emailed the owner who gave me a very backhanded 'I can see how someone could be offended by this! kind pf reply. I replied explaining that it really put a dampener on my birthday nd that no professional establishment should talk to potential customers that way, asking him for his thoughts. He hasn't replied...

I feel I should take it further but don't know what to do. Maybe I should just man up...?