In Marketo, for picklist values on a webform, if we decide to not have 'displayed values' but only 'stored values' in place so as to not affect the backend (SFDC), what are the implications? For e.g., if we decide to remove United States from the public facing website to comply to certain policies but have the country in SFDC or any backend that Marketo is synced with, what are the after effects to the bi-directional sync of leads between SFDC and Marketo?
For the future records, there will be no implications. What about the ones that already exist in SFDC with the country 'United States'? Will the CRM sync have any effect on that record if there is no displayed value but stored value to the record?
Thank you in advance.
There is absolutely no direct link between the picklist values displayed in forms, and the values in SFDC picklist fields.
The only risk you might have is that if you capture in a lead form some (Stored) values that are not supposed to be inserted in SFDC and IF the SFDC field is set to strictly enforce the values, you will not be able to insert the lead in SFDC or update if it was already sync'ed.
Just to expand on Greg's response, there is no link between the displayed values on Marketo forms and the values in Marketo fields, either, let alone the values in SFDC fields.
Marketo only cares about the stored values (what Form Editor calls "server values"). The Marketo forms processor has no idea what you displayed on the form in a dropdown: it literally is not passed to Marketo at all, only shown to the end user.