Why Free Bonus Money Is Rarely Free
Because a wagering requirement converts the bonus into a volume of play, and volume of play is exactly what the operator earns from. The offer is not dishonest — the terms state all of it plainly — but the headline number and the real value differ by a factor that most players never calculate. Doing the arithmetic once, on any offer, tends to change how the next one reads.
There are genuinely good offers, usually the small ones with low requirements and full game weighting. They rarely appear in advertising, because a modest bonus with gentle terms is a harder thing to put on a banner than a large one with hard terms.
The Simplest Policy
If you were going to stake that much anyway, take the bonus and stay under the maximum bet. If collecting it would mean playing more than you planned, decline it — the clean cash balance is worth more than the conditional one, and there are no clauses to accidentally break.
The turnover arithmetic behind all of this is on the odds and house edge page, and the guide index is on the home page.