Mankak, not quite! " A lot of " and "lots of " do not always take a plural verb. So we would say " There was a lot of trouble" " A lot of trouble was caused" " A lot of material was used". We'd also say " Lots of money was spent " and "Lots of time was wasted". In none of those cases is "were" correct. That's because we think of the subject as being singular (trouble,material, money, time ) and it doesn't matter whether 'lot' is singular or plural. 'Lot' or 'lots' is not being thought of by us as the subject
So what of people ? When I wrote "There was a lot of people" I was thinking of 'lot' as the key word, the subject, just as if I had written "There was a crowd of people". I meant there was one group, one lot, of people all in one place.For the answer "In the stadium, there was a lot of people" I would not have written " In the stadium there were a lot of people" ( because "there were.." is plural and 'a lot' is singular and I'm thinking of 'lot' being the subject ). If I wrote "Lots of people..." I'd put 'were' because there I see the key word, the subject, as lot but in the plural, lots, so it takes 'were'. "Lots of people was..." is patently odd and wrong.
We have this trouble all the time in English over thinking singular or plural. " The committee meets on Thursdays. They could not agree in their meeting last week" makes sense because in the first part we are thinking of the committee as an 'it', one body, but in the second we are thinking of it as several individuals, comprising the committee, who could not agree among themselves ! As a matter of style it would be better to make both parts plural . .