I'm not sure I completely understand your reply, but it seems as though your saying just let TempDB grow as needed.
TempDB should be sized just like any other database. One should know their workload, or at least monitor the TempDB over several weeks to see what is a healthy size for it. Once this is determined, you then can set the size of the TempDB, so that when the server is restarted, it will be at the correct size, thereby having to use "auto grow".
"auto grow" on TempDB and other database can cause serious performance issues, and only be used as a safety net.
As far as "repopulating" TempDB being important. What would it be repopulated with? This database only exists for temporary operations. Once a connection is closed any "temp" objects created (tables, views, etc..) by that SPID will be dropped. TempDB doesn't store query cache, execution plans, or stats. A restart of the server flushes the cache, memory.