It is true that many have been told it won't work since no one has ever done it before. (Wright Brothers)
But this is not the case of flying the first plane or landing on the moon. This has been done many times. Some were successful and many were not.
It's easy to point to the success stories and tell you to hold on to your dreams. It's another thing to take real life experience and evaluate whether or not this is a good idea.
I like the some of the advise given above. I would make a small edit however.
Be prudent, do your homework, think outside the box, but above all, hold onto your dream.
Be prudent, do your homework, think outside the box, but above all, don't be too proud to let the dream die.
There is no intrinsic value in a dream. It won't put food on the table. You can't sell it. Don't place more value on a dream than what you can sell it for.
Life isn't a Disney Movie, follow your heart and your dream and you'll end up broke in a cardboard box. Use your head!! And by all means Go For It if it makes good non subjective sense.
One last thing. Specializing in something is great. But you need to have a general draw to get people into the store. Or the other option is to not have a store and save the brick and mortar cost.
"A generalist knows less and less about more and more until eventually he or she knows nothing about everything. A specialist knows more and more about less and less until eventually he or she knows everything about nothing."
While this is kinda funny to think about, it has some good truth in it. Unfortunately most LGS's fall into the first category.