Imagine going to McDonalds or something, buying a couple hamburgers and seeing PayPal on your credit card statement instead of McDonalds. Sorry, but it just has unprofessional written all over it. You have a "company" who can't or won't get their own merchant account?
You're comparing a physical product with a virtual product. Paypal is considered the "norm" in online transactions. Most people have a paypal account and/or deal with paypal on a regular basis.
Not accepting Paypal in the lower-end hosting industry is comparable to only accepting cash payments at a McDonalds, you end up cutting out quite a bit of business that you cannot afford to lose out on.
I agree it looks far more "professional" to have a proper merchant and accept cards locally and being PCI compliant and all that jazz, but your AVERAGE webhost in the low-end sector doesn't have any of that, and wouldn't likely be able to reliably secure your personal information (IE the cVPS hack, or any of the other WHMCS related hacks where the CC information AND CC hash has been stolen).
HUGE companies such as Amazon, Newegg, etc offering paypal for convenience but not as their primary payment gateway makes sense. Fact of the matter is, the expectation in the low end sector is to run off of Paypal. If you expect paypal to be there, then you're likely going to use it for convenience and piece of mind. Should it be the ONLY payment gateway? No. Will it be the vast majority of your payments unless dealing with larger contracts or businesses as opposed to the end-consumer in the low end market? Sure.
Am I willing to trust a low-end provider with my credit card information? Hell no. I'll trust my datacenter with that information, but not a company selling primarily cheap end Virtual Private Servers. There's piece of mind knowing a low-end provider uses something that doesn't store credit card information locally but passes it via JS to a service that handles all of the security features for the company I am purchasing from.
We offer a Credit processing payment option for those that do not wish to use Paypal, cannot use Paypal, or prefer to deal with cards rather than accounts such as with paypal. We're all about options, but expectations are that paypal ends up being the most used gateway as it's essentially an industry standard. If you use our credit processing then GREAT, I am very glad we are able to offer you an option. If you use paypal, that's great too. Either way we're getting paid and you're getting a service.
TL;DR: Paypal is the accepted industry standard in the hosting industry, specifically talking the low end sector where you're buying cheap end VPS, renting dedicated servers, not paying for colocation with a datacenter. Sure people use other methods, but the vast majority is paypal.
I don't have a merchant account through my banking institution. Am I not a
legitimate business? If so, what makes me non legitimate compared to your company?