Rooney blossomed with the added responsibility and moved third in United's all-time goalscorers list with a brace in the 2-0 win, with the first a 58-yard strike reminiscent of David Beckham's famous goal against Wimbledon in 1996.
"Wayne has led by example all season," Moyes said of his frontman
"Maybe wearing the armband, taking a wee bit of pride in wearing that, to show exactly what it means.
"He wants to take responsibility and I think you always want players who take responsibility.
"It's [that] sort of magic why you talk about the top players so much.
"Wayne scores two goals at West Ham and that's why, players of this ilk, you write about and talk about more than many others."
Rooney's man-of-the match display at Upton Park will have no doubt boosted his chances of becoming United skipper.
The England international recently spoke of his desire to lead both club and country - something that may well happen at Old Trafford at least with current United captain Nemanja Vidic moving to Inter Milan in the summer.
"You get opportunities in football, even if you're a player out of the team suddenly you can get a chance," Moyes said.
"Or if you become a key player and then get the chance to wear the armband and take that on
He did that
He showed that against West Ham as well.
"I've said there will be no decision taken until next season, but we had injuries to Rio [Ferdinand], suspension to Vidic, injuries in part to [Patrice] Evra so we decided to put him on the bench, and I thought Wayne picked up and did what he needed to do."
As well as Rooney, Moyes picked out Juan Mata and Marouane Fellaini for praise after United followed up victory over Olympiacos with another win at West Ham.
Back-to-back victories have brought renewed confidence and will likely prove a timely shot in the arm ahead of Tuesday's derby clash with Manchester City.
"We go in after a better showing, if we play as well as we did at West Ham then we will make opportunities, we'll make chances," Moyes added.
"If we play with the same heart we showed against Olympiacos then we'll be very hard to play against and have a big spirit in the game."
Source : PA
Source: PA