You might have 50 years of retail experience, but you /do/ still have
something to learn. Far less than most people, of course, but if you
think you know it all, you have misunderstood a lot.
Your specific recommendation was to visit the shop to make use of their
time, resources, stock, staff time, etc., with /no/ intention of buying.
That's very different from window shopping, or just looking around for
something of interest, or on the chance of buying something.
If you have been working for 50 years in retail, you know it is a
percentage game. A certain percentage of people visiting the shop will
buy things, and a certain percentage of what they pay will end up as
profit at the end of the day. Your job as a shopkeeper is to match this
up so that the averaged profit justifies the cost of having the shop,
stock and staff. Sometimes it's fine with zero chance of buying, or
with zero (or even negative) profit - if it increases the chance of that
customer buying something else in the future, it's a win overall.
But if someone that has a zero chance of buying, and is specifically
aiming at finding information in order to buy from a competitor,
especially an on-line shop, you lose out. If it is a "normal" customer
looking for a monitor, who doesn't find out they want, that's okay -
they'll see other things of interest, and maybe they'll buy at the time,
maybe they'll come back in the future. (Or, as you say, maybe the
service, price, etc., mean the shop doesn't deserve the custom.) But
for a customer planning on doing their purchase from the cheapest
internet site they can find, all the ideas they get from /your/ shop go
to the competitor.
This effect is a huge problem for some types of shop, especially for
small and independent retailers. /Real/ bookshops are disappearing
fast, as are record, CD and DVD shops. Stand-alone computer shops
(rather than combined service/sale shops) also suffer from this problem
- the result is that to cut costs to compete, they often cut quality and
service.
You can say this is changing society, rather than the fault of the
customers. And you can say that resisting it - by buying in the shops
you look in, and paying more for better service - will just be a drop in
the ocean. But society is made up as the sum of such drops - and it is
in the long-term interest of everyone to protect real-world shops.