In case you hadn’t noticed, the media is ablaze with fascination for the upcoming royal wedding. The union of Prince William and commoner Kate Middleton is essentially a ceremony in another country involving an institution Americans rather emphatically rejected way back in 1776. Do Americans care about this? Or is this just a media frenzy, not unlike the pre-Oscar hullabaloo for a film nobody bothered to see?

My wife believes, as she does in almost every matter not related to the workings of the TV remote control, that I’m completely wrong and wrongheaded about this. Everyone loves a wedding, she insists. And everyone wants to see the dress.

Her take on things certainly explains why Meredith Vieira and Matt Lauer host “Inside the Royal Wedding” (7 p.m., NBC). Or why the Bio channel is repeating the 2011 Lifetime movie “William & Kate” (7 p.m., Bio), starring Camilla Luddington, followed by a full-fledged “Biography” (9 p.m., Bio), titled “Kate Middleton: Uncommon Bride.” BBC America repeats “Prince William’s Africa” (7 p.m., BBC America). It’s about the young man’s visit to Botswana. But the title might infer that the whole continent belongs to him and him alone.

But even if you find the royals less than fascinating, it’s impossible to deny the devotion of their subjects. At least some of them. “Extreme Royal Collections” (9 p.m., TLC) visits with three women who have taken Windsor-mania to near “Hoarders” levels. British-born Margaret has more than 30,000 commemorative teacups and other ephemera. A wealthy American collector has spent upwards of six figures on royal gowns dating from Charles I to Princess Diana. An Australian couple has established a bus-tour destination/tourist trap with their vast assortment of royal kitsch.

Perhaps the oddest moment of “Collectors” is when Margaret stands besides a life-size wax dummy of Prince William and confides her best wishes toward him, his fiancee and his family — his mother and grandmother in particular. Even Margaret recognizes that she’s talking to a waxwork, but there’s nothing insincere about her affection. In that moment, it’s easy to understand the particular if peculiar pull of the royals. For all of their foibles, they embody a powerful combination of the religious and the patriotic, with a large dose of celebrity thrown in for good measure.

The dime-store idolatry on display here reminds us that some saints, or at least their statues, are more popular than others. It’s safe to say that the demand for Diana ephemera remains healthy, while Camilla and Charles trinkets gather only dust.

Tonight’s other highlights

• The top six croon on “American Idol” (7 p.m., Fox).

• Auditions continue on “The Voice” (8 p.m., NBC).

• Intimacy and mortification on “Modern Family” (8 p.m., ABC).

• Revenge of the nerds on “Breaking In” (8:30 p.m., Fox).

• A strange signal on “Criminal Minds: Suspect Behavior” (9 p.m., CBS).

• A killer hits Raylan where it hurts on “Justified” (9 p.m., FX).

• “South Park” (9 p.m., Comedy Central) enters its 15th season.

•”Clean House” (9 p.m., Style) begins a new season.