ELASTIC FOOTING OPTION IN STAAD PRO.

Hi,

Could you please answer the following questions, 

1) Do we use ELASTIC FOOTING option to model the isolated footings supporting the column members using soil sub-grade modulus?

2) Do the most people use this option?

I have seen many times people defining FIXED, PINNED OR FIXED BUT type SUPPORT to support column members.

Please see the screenshot attached from the section 5.27.3 of TR-Manual.

Thank you