The tomatoes sold cheaply in supermarkets here in the UK are almost universally watery, mushy garbage, grown fast and cheap under intensive conditions in Spain, Morocco, Senegal, etc. and yanked from the plant before they have a chance to develop any flavour at all.
Of course, all these supermarkets have their own brands of "premium" tomatoes - often domestically grown - and these are generally much better, but the cost is usually in the region of 150-170% of the standard fare, and even more if you want them organically grown. At this point, the tomatoes are more expensive, by weight, than "budget" (i.e. intensive farmed) chicken breasts.
You've heard it all before: we (and North America and parts of western Europe are the worst offenders here) don't accept that produce is seasonal any more, we want everything available all the time at rock-bottom prices. Something has to give, and sadly that thing is usually quality, which with food means flavour, aroma and texture.
I have no problem with GM as a technology. As a means for multinational bio-tech and agri-tech companies to control and extort money from farmers, I do have concerns. That, however, is another issue entirely.