By all means, if you want to work for FR that badly, go ahead. If you value 738 hours that much you won't find an easier airline to get into at the moment. I suppose they make a pretty penny on all those in-house TR too.
My personal issue with FR is this; you're working for free and losing out on income. You pay for the TR, you pay for various miscellaneous things, and you lose out on income while you're on reduced pay or not paid at all. If you plan on leaving after 18 months, you won't get close to breaking even with someone that for example went the turboprop route. If anything, I just want people to project their income ahead of time and compare the options!
A personal anecdote: A colleague of mine during the MCC course already had a job offer on an ATR, bonded TR, due to start in 3 weeks later, as a regular employee earning an honest salary (36k€ i believe?). Instead, signed the dotted line with FR and is now waiting for the TR. Apparently he values 738 hours an awful lot! After those 18 months you mentioned, He would have had more money in his bank account, a solid amount of TP hours in his logbook and actual IFR handling experience flying in the thick of it. I am not convinced that 738 hours are the only valuable commodity in this industry.
To each his own I guess. But as long as there are alternatives, or if you're clever and got another education besides flying, I don't think people should be so keen on flying for FR!