The prices for broadband bandwidth at data centers are sometimes as much as 10x higher than for a typical small business/consumer connection, at least where I live. Now, I understand those are two differend kind of products, but what exactly are the differences? Is it mainly because the bandwidth you get at a data center is guaranteed (CIR), while a consumer offer lists maximal bandwidth (EIR/MIR)? Or are there other factors as well?

(Note: my previous, much more specific question on the same general topic was closed as not constructive. I tried to extract the core issue and present it in a way that can be answered objectively. If you feel that this question is still bad and should be closed, please care to comment and explain why.)