Contractors do get paid more but they don’t earn more at least not anymore after IR35 since they have a tax rate that is over 50% as they are also liable for the 15.5% employer national insurance contributions now.
Overall contractors are far cheaper in the UK even at day rates of over £1000 and replacing people that earn high 5 to low six figures.
They aren’t paid any bonus, there is no pension contribution there are no benefits and there is no liability for redundancy.