Ps, I think some of you don't know what I mean. Customers can already pay via Card/Debit card directly on our website because we have a merchant account with PayPal and so, in that case, we don't need anything else. But different card processor offers various methods.
For example, if a customer pays us using credit from their PayPal account then the credit is available right away, but if they pay by card, then those funds do not clear for 30 days due to PayPal having 30 days rollover.
WorldPay told me that payments clear with them within just 3 days, plus they have lower fees, etc.
So there is a good reason to use different gateways/processors.
I wouldn't go as far as to offer 40+ different payment methods like some providers do (unless you have a large HR dept) but having <5 is ok, even for smaller businesses.