highkick05
The purpose of the addon is to provide simple configuration (ie copy/edit files) of WebGrab+Plus.
If you delete the service, you break the addon.
If you do not need the service, you do not need the addon.
As an alternative, you may use the packaged version of WebGrab+Plus that I maintain and that underlies the addon: GitHub - awiouy/webgrabplus.
If you download master of that repository (eg with cron), you will get the versions of WebGrab+Plus, siteini.pack, xml_time_correct, WG2MP, etc. used by the addon.
Note that this requires the Mono addon, and configurations are tailored for /storage/.kodi/addons/service.webgrabplus (see the file layout of the addon).
You will then be free to define your own automation/scheduling
As for tvheadend (ie a consumer), it is out of the scope of the addon
I hope you will find it useful