I must say I've never experienced this, and I use the pay lounges quite a bit. I've had maybe a 20 wait at peak times at No. 1, usually on morning flights I'll just walk in. In the South Terminal my usual non BA routine is to go to Pizza Express and have the light breakfast and a coffee (the breakfast seems a little less generous than the old Grain Store one), or a pizza depending on the time of day. Then No.1 to have snacks and drinks on hand while waiting.

In the North Terminal, I avoid the Breakfast Club, which is the PP restaurant because the service is atrocious and the food not great, but usually head up to Plaza Premium. I've never had to wait. It has a decent spread and also has toast and marmite available which for me is a major benefit. Plus beer on tap for those who like beer (I do, but not before flying generally), so you don't have to queue at the bar or worry about drinks limits.

Gatwick is nowhere near as bad as, say, Stansted, for lounge availability. Luton is great, not least because there are three restaurants taking non Amex PP. You get used to the bucket and spade atmosphere.