|In essence, they are. |
An input of 4 for a 15 weight is not as "important" as an input of 4 for a 20 weight - 12 vs 16 in the final calculation.
The only other way to make one question more important than another would be to have (for example) 1 - 5 as the available inputs for one question and 1 - 7 as the available inputs for another.
That's a lot more complicated especially if you are assigning text to the inputs (Very Unhappy, Somewhat Happy, Estatic, etc.)
It's also easier to modify the survey by changing the questions and the associated weightings than it is to change the questions and the number of available inputs.