Commercial photography in private places might not be allowed in certain places. Who you are, as said, is irrelevant. Relevant is either that you are taking a picture susceptible of commercial use (tripod, large format) or, more in general, the use of that picture.
If you sell prints as "fine art", not in series, that's not considered in most countries commercial use, even if you sold them at $5000 each.
"Commercial" has two common definitions: the broad one, "selling for publication", and the narrowest one, "selling for advertisement".
So the entity owning the place where you open your tripod might object about having somebody making pictures destined to illustration of textbooks, postcards, calendars, guide books, magazines, that stuff. People is generally happy if their property ends up in a magazine, guide book etc. But you can have the case where said entity wants to sell postcards, calendars etc. and have an exclusive on it. Disneyworld wouldn't like you to open your tripod in their premises, not even for postcards. An Hotel would probably not object to any use of this kind.
More likely, the entity wants to restrict "commercial" use as in "use for advertising something". That's because it might appear that the entity is somehow endorsing the product, and you can be sure that any entity will either not endorse a product, or want money in exchange for the endorsing.
In any case, your "status" as a photographer doesn't mean a fig to them. The entity typically looks at your camera. If it looks "professional" i.e. if it is big, think a big digital and if you use a tripod then they will stop you. If you use a digital point & shoot, they will not. That means you have to use a film camera, with high ISO film is necessary, hand-held, and you will get professional-quality results without being bothered by anybody
Fabrizio