> 24 million people receiving benefits (aka cash) in uk

It looks like most of those people are claiming State Pension / Pension Credit. Which doesn't make it not true, but it's maybe not what most people will think of first when you talk about benefit claimants.

That source doesn't cover the claims you made.

Spending is paid for out of tax and all those people will have paid tax. Paying less tax than someone else doesn't make a free rider. Deliberately opting out of an obligation while taking from the group makes a free rider.