Check this page especially what is written at the bottom with a brown background.
My Account: Premium Account - ClixSense
Upgrading your account will not get you more offers or tasks and may not increase the number of ads available. The only added benefits are listed above and if you are not going to refer others or won't be able to complete the daily checklist on a regular basis, upgrading may not be for you. Please make sure you understand this before upgrading.