They won't scratch their whole ERP system, but they will surely think twice before licensing any of SAP's new shiny applications. I have seen that happen, customers that start buying line of business solutions from different vendor, just because they don't want to be more dependent on SAP. Other customers start removing process by process from SAP, to a point where SAP becomes replaceable.
Don't underestimate the problems IT directors face when they need to ask for more money to do something that should be included in the maintenance fee.
It's all about the customer experience 
.