Extended-Phenotype It is an obsession, yes - but it has roots. In general (not always, obvs) players on frees aren't as 'good' as players with contracts, and if a club is competing for the services of a contracted player who costs X amount of money (and still requiring wages) it shows they are more up for sticking their hands in their pockets, which means they are looking for more of a return (hence 'ambition'). It's a crude way of looking at it but not without justification.
Clubs spending more money is a sign of intent, whereas clubs being a bit tighter can be a sign they just want to make do. That's not to say a tighter approach will always see less success but some players are in contract and cost more money for a reason.
Wage budget is a far greater correlation to success. And our record with big value signings is poor.
Fees spent is a terrible way of judging success.