i'm probably using an informal fallacy but if online advertisers earn hundreds of billions of dollars, someone must be finding some return on their investment.

i might be wrong, it might just be a huge grift, but i dont know how to come to that conclusion

My suspicion that is a huge grift ? This is what I want to find out. I know very little people in my social circle that used internet ads successfully for their business and very little that found them useful at all