My opinion on this is going to upset some folks.
I would say in both cases you encountered the typical sleazy dishonest fly-by-night dirtbags who specialize in ripping people off. If they had to it is highly likely they would be able to create anything fresh out of the box for the simple fact they don't know how.
The majority of con men out there calling themselves developers do this, so yes they were 100% right when they said it is pretty much standard practice... and that's a massive problem in this industry right now!
Site owners are slowly starting to wise up to this, but in general because the normal person doesn't know anything about HTML, CSS, JavaScript, accessibility, emissive colourspace, or any other aspect of building a site properly, it becomes ridiculously easy for these two-bit scammers to saddle people up and take them for a ride.
This situation is often only exacerbated by the fact most of these off the shelf templates they start with are themselves poorly coded and developed, and in fact could be telling large swaths of your potential visitors to go such an egg. As these jokers themselves slapping together and modifying these templates rarely have the proper knowledge of the underlying languages, they're unqualified to even know if what they are handing you is garbage or not.
... which is why I have told more than a few clients the past five or six years to sue for damages. Particularly if they did something like use an off the shelf template and didn't tell you that's what they were doing.
It's one thing to tell you they're buying off the rack, it's something different entirely when they do so and then have the nerve to call it bespoke... since then it's not even tailored. For all intents and purposes such "developers" little more than glorified alterations ladies.
You work with print graphics? Great, you'll know exactly what you got then; you didn't get artists or an artisans, you got plagiaristic tracers. The guys who brag about what great artists they are when everything they've ever done has been paint-overs of magazine cover photographs.
... and whilst yes, that is pretty much industry standard, that doesn't make it right. It just means they're part of the sleazy fly-by-night scam artists who have destroyed any sort of ethics, morality, or decency in the industry.
It's something I'm always saying, always pointing out, and always fighting against no matter how many people that might upset for the simple fact that it is dishonest, two-faced, and nothing more than outright con-artistry.
Simply put, anyone telling you to use Wordpress for business doesn't know enough about websites to be making them for businesses. Anyone who uses off the shelf frameworks or templates and has the brass to claim that it's a custom solution is bald faced lying. The people using these broken, nonsensical practices on the whole basically are nothing more than predators, taking advantage of your ignorance so they can charge you several thousands for work that I would feel guilty charging $50 for.
Just be thankful you're not working in healthcare, banking, public utilities, or government agencies where the typical results of these sleazy shortcuts can land you in court with four to six digit fines per DAY. Because the folks who slop together these ready-built answers don't know the first blasted thing about the underlying technologies they most often result in sites with major accessibility violations, which in certain industries and types of sites can run afoul of contractual obligations, or laws such as the US' ADA or UK's EQA.