I think it is respect for the local population in the countries the rally competitors are travelling through that should be the most important factor. It is widely acknowledged that tired drivers are potentially dangerous drivers, so you have tired competitors/ support drivers driving on the same roads as the locals.
In polar or mountain climbing expeditions - the expedition group members actions usually do not have a direct effect on the local people unless they are a paid (usually) part of the expedition.
The Dakar has an expensive entry fee, many amateurs can only afford one event so some are likely to take risks to get their finisher's plaque/ statutette.
Motorsport deaths usually get a greater media bashing than other sports ( for what ever reason) than skiing, snow mobiling, mountain climbing etc deaths.
If someone wanted to do a long distance rally for the spirit of the event won't they be still rate the African rally that actually still goes to Senegal the more worthy event ?
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