I assume from your spelling of cheque that you are probably American or Canadian. (Especially as I can't think of anywhere else other than Britain and Australia that's still using cheques.)
But we’re talking about Spain.
As
@Kathar1na posted elsewhere, the cost for a DEBIT card Transaction in Spain is 0,2%, or just 2 cents for every €10. Which is why Spaniards now use them so freely.
Please note as others have mentioned elsewhere this is a RECENT and rapidly growing trend i.e in the last two or three years ( since covid).
A CREDIT card is considerably higher , at around 6 or even 7%, depending on the bank
I think you missed this:
“True, but with the new chip cards it's extremely hard - theoretically impossible (but I'm always slightly sceptical) - for them to be compromised.”
Older card’s were indeed often compromised.
And as to your point about them having to strip you, believe me, in some countries (NO, I’m NOT talking about Spain), that’s exactly what they might do. They know all of our ‘tricks’ - many will even know more than I, and believe me I have researched this extensively because I've travelled extensively. They check all obvious places - waist, neck, foot etc. If you're lucky they won't wrench/ cut your foot removing the foot wallet.
But I admit that in Spain it's a reasonable precaution and highly effective. Robberies in Spain are extremely rare -especially of pilgrims. The vast majority of loses are simply opportunistic thefts and in that regard you're protecting yourself well.