Looking on the internet deeply has found these results:

there were less people in the shop today is the most popular phrase on the web.

there were fewer people in thexshop today 10 results on the web	there were less people in the shop today 112 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong with it. Like so many �... There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong with it. Like so many �... There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong with it. Like so many �... Dec 24, 2014 ... There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong�...

there were fewer people in thexshop today

10 results on the web

there were less people in the shop today

112 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong with it. Like so many �...
There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong with it. Like so many �...
There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong with it. Like so many �...
Dec 24, 2014 ... There were less people in the shop today. Both are right. Many people frown on less with count nouns, but there's nothing technically wrong�...