i gave up parking in msa,sa long time ago,( how do you get a good nights kip in them places ).ind est or long out of the way layby does it for me… pint of milk n morning paper is all i would buy from them aswell. rip off gits… 
I park in a MSA perhaps once or twice a week and never pay. My boss throws the parking tickets straight into the bin. I cook myself and although I do use their showers, the trade off is that I buy my daily newspaper, thats all.
They are a rip off and not geared for the everyday working man, just the business man who calls and puts it on expenses.
The situation must improve…
MSA are Rip off!!! 
but best thing to do - buy a tool box for trailer then fill up the foods and drink in the box. you can cook the food (same way as foreign lorries drivers do that)
I agree with most MSA’s are a big no no for use knights of the road! far too expensive, crap food, no security, too many salespeople!
All industrial estates should be made to provide overnight spaces for trucks with proper facilities! by that just a tap and toilet would be a good start!
I can remember reading a leaflet at one of MSA,s about the reason for MSA,s higher fuel prices,this gave a list of about half a dozen “excuses” .
The first of which was “Remote Locations and Inaccessability of Sites”!!!,what easier place to deliver to than MSA. Talk about make the rules up as you go along,also breaking down in an MSA and being told when the firm,s fitter arrived,“you cant repair it here ,you’ll have to pull out onto the hard shoulder”!!
regards derek