That's exactly the real and only issue + pricing as a consequence, everything else is horse crap from owners their mouths. There is no issue with increased costs that much on food at all, neither on rent or utilities, let alone with wages. Owners use this now as an excuse, as indeed, that now became the last margin to be able and tweak AFTER starting way too many of the same businesses everywhere. This is a undeniable fact all over Thailand.
Just look at Chiang Mai for example, all used to be 80% focused around the old city quarter and up to the river. Now you have over 5-6 main areas far from each other. Then look at tourist figures, there is dozens of millions tourists more than in the old days. So even people went out less often, this should never be the issue.
The real issue is that prices are way too high, and restaurants say that they can't lower the prices is only due to the fact that there is too many restaurants. I mean explain to me why I can get for the same price a tenderloin in Australia with way higher rent, way higher taxes, wages and everything. If you want to tell me that is only because of the higher tenderloin cost, just clueless. I know what they cost wholesale.
It is the volume of sales that is the issue, and that is a result of being over priced. Restaurants used to have constantly 5-10 people from opening to kitche close, if not a full house around the busiest hour(s), by default. That is what restaurants are supposed to do.
In Thailand it like became the normalized standard that you run a business where you get a handful of customers, and that that is needing to make your money. Yeah indeed, then you can only keep increasing prices and if you then look at statistics, the tweaking and margins would be tight.
It's the exact same with freelance girls and alcohol in bars too. So how did the freelance girl get higher costs then? And last but not least, why are restaurants that do sell cheap + always full, make money, are able do to it the right way?
Meanwhile somewhere on an island: I still get my beers for 60 baht, I still get large Thai portion meals for 50 baht and so on and on.
If you sell Thai food for 150 per meal and then they get only 10 customers, they make 1200 baht. The cheap place gets customers all day making just 30 baht per meal, still will walk home with 2000-3000 baht. So with other words; anyone can sell cheaper if they had more customers.
If I tell a restaurant i can get a group of 10-20 people and want 5-10% discount it is also possible.