I am classified as a 'newbie'. I am not sensitive about it, and it's fine, because I have returned to fish-keeping after 20 years, and things have moved on so incredibly, that I know I have a lot of new stuff to learn. But I kept tropicals for eight years before I reluctantly gave up. Work it out, people - I started well over 25 years ago, when things were (in hindsight) very primitive! The knowledge now (freely shared) is awesome!
We had the (limited) advice when we started of a friend who kept fish. But I bought lots of books (there was no internet), and started with a community tank, which I set up, installed an undergravel filter, filled with plants, and ran for a fortnight before the guppies (a cory, some platys, and damn it all, a CAE!) were introduced. It was all we knew then.
I moved on to kribensis (which bred) and Oscars (which grew enormous - at least they must have been fed right, and had enough room!).
So many points made by so many people of so many ages and so many different experiences, all make at least SOME valid points.
If you are buying it, it is YOUR responsibility to research it, if only to save yourself (and possibly your unwitting purchase) any grief.
Would you buy a car from a showroom on impulse, without knowing what it consumed, what it cost to run, what insurance group it belonged to? Of course you would not!
A car salesman is only too happy to sell you a car! Caveat emptor! Yet a fish is NOT an inanimate object! Buy him, and you have a responsibility for a life.
The question is, how seriously do you take that responsibility?
Sadly, people buy 'pedigree' puppies from unscrupulous sellers, without knowing characteristics of the breed. That also is a life, potentially ruined if s/he goes to the wrong home.
So, it appears that the only difference to the careless purchaser is in the price, and what it will cost the purchaser if it goes wrong.
I have the occasional (very occasional - three in 25 years!) litter of puppies. Prospective purchasers are grilled both sides. I regard that as my responsibility. But many people breed for 'profit' (yeah, right), and if you have the cash, they will pass over the puppy without question. But if you have problems, they will also deny any responsibility or liability.
Clearly, this can be used as a parallel for the purchase of fish.
Sales people generally are exactly that - they will sell. If they are paid on commission, the more they sell, the more money they make. If they are not paid on commission, any sales still look good on their till record. If they are paid peanuts, they will generally agree with anything you say, just to get you out of their hair. And of course there are exceptions to this, we all know them and we have all come across them - just not that often.
It is up to you to research so that you know if they are bulls******g you when you ask questions.
Enthusiasts are something different. They will advise, and sell you what they know you can deal with.
In the end, it is the responsibility of the buyer. Ask questions, but go home and get on the net and research!
And yes, I agree - in my limited number of forays around this site, I too despair of the questions 'can I do this?' 'no' 'well, I am going to anyway'!
The original post was an excellent prompt to make people THINK about the consequences of their own actions!