Really? Your one experience is strong enough to qualify as proof?
How many bachelors in Sociology do I need to get to prove to myself?? I took at least 15 classes in Sociology, and got 1 -A and the rest A's. Those of us who get degrees in a science have to take not just our major courses, but also other science courses too like, Physics, Chemistry, Organic Chemistry, Calculus to satisfy our degree requirements. Sociology majors at my university didnt have to take these level courses, instead were able to take courses like applied statistics and business math to fulfill their requirement.
Like I said before, "That is proof enough to me" that a Sociology degree is "fluffier"...If I compared the difficulty of my advanced microbial genetics course to my concepts in sociological theory class, well...the later was just cake in comparison.
I took Sociology courses bc I was genuinely interested in it, and that probably reflected in my performance in the coursework.
Also, just want to point out that I am sure there are people who were Sociology majors who also had a hard time writing declarative sentences and couldn't perform qualitative research. As I am sure there were Sociology & Biology majors who have no clue how to apply the Hardy-Weinberg equation.
You wouldn't need multiple degrees in Sociology, but your anecdotal experience isn't necessarily reflective of all experiences of all majors at all levels of university. If anything, it's proof that the major at your school is fluffier. For what it's worth, my university did require calculus of Soc majors, in addition to statistics (same stats class required of the science majors), as well as an upper division fieldwork or advanced statistics course.
In any event, it's obnoxious to criticize anyone's major choice, so I'll just leave it all at that.
My poli sci program required stat, calc, two quantative anylsis classes,macro and micro economics, and a science class within the major. I woudln't consider that fluff. But that's just me... Some schools might have fluff social science programs, but not all.