Four points:
1. The difference in prices between , say easy and BA is not just due to a meal. This is a myth perpetuated by the marketing departments of some budget airlines. In the US (correct me if I'm wrong) southwest provide free coffee and snacks.
2. As for budget airlines taking slots at heathrow, this is simply a nice piece of spin. Belfast to LHR with a budget carrier would be expensive. For many many reasons, which most in this industry already know, LHR is expensive to operate from whether you are a budget carrier or not. Easy 'fans' somehow think that easyjet can make the same level of fares profitable from LHR as they do from luton. It really isn't so.
3. If you are a 'fan' of budget airlines always do check the fares on other airlines, as you will frequently find cheaper fares. If you only ever book a flight via one budget airlines website (because they say they are cheaper) without checking other flight prices then you are a fool. Their is no point in quoting fares here, because people from the respective marketing and sales departments will just quote cheaper fares on other routes. I recently got a quote from a so called'traditional'(BA) carrier which was almost £100 cheaper than Ryanair. If you really want a cheap flight check out the prices available from all the airlines (including budgets) serving the route, otherwise you will be ripped off. No one airline is always cheaper (despite what you may hear), always check out all prices (pretty easy on the net).
4. The reason why people have 'had a go' at certain budget airlines recently is because of the way in which they have treated staff, and the crass way in which they have used redundancy of many airlines ataff to gloat about 'success' (shareholder hype). Last night on TV, the staff on a cruise line were shown to be paid £1 per day, and relied on tips and very long hours to make a decent wage- there is at least one budget airline I could think of who would do this if given half the chance.