1. Trains don't go everywhere. You still need trucks to get things from the train station to the warehouse.
2. Who said anything about subsidizing anything?
1) I am in the UK where trains used to go within about 5 miles of just about everywhere except in the Scottish Highlands, and the railways operated local delivery trucks for the doorstep delivery of goods. Places that warehoused, produced, or consumed bulk stuff were located near to railways and had their own sidings for loading. There were vastly fewer trucks on the road, and what there were were quite small. Roads were pleasant places for people living by them, children playing in them (yes), cyclists using them, horse riders using them, and motorists using them.
The system worked well until the railways were all but crippled by poor maintenance by the ends of both WW1&2 (co-inciding with the knock-down sales of ex-army trucks to de-mobbed soldiers setting up road haulage companies), followed by nearly all but the railway main lines and main stations being closed in the 1960's.
2) Trucks are subsidised in the UK by paying vastly less in road tax than would be proportional to the road wear they cause, the distance they travel and the strength to which bridges need to be built. They are subsided by the road tax on cars, especially ones like my wife's, who only drives about 600 miles a year.