Is the apparent dichotomy between bursting activity of magnetars and radio pulsars real?

Anomalous X-ray Pulsars (AXPs) and Soft Gamma-Ray Repeaters (SGRs) are a class of young neutron stars (NSs) characterized by high X-ray quiescent luminosities, short X-ray bursts, and giant flares (for SGRs). They are believed to be magnetars, i.e. NSs with magnetic fields ∼ 10¹⁴ - 10 ¹⁵ G. The discovery of magnetar-like X-ray bursts from the young pulsar PSR J1846-0258 [1], with an inferred surface dipolar magnetic field of B_p = 4.9 × 10¹³ G, lower than the traditionally considered magnetar range, and, more recently, by the discovery of SGR 0418+5729 with an even lower B_p = 7.5 × 10¹² G [2], well within the range of the rotation powered pulsars which do not display any bursting behaviour, has raised the obvious question: why some "high-B" pulsars (PSR J1119-6127 and PSR J1814-1744, with B ∼ 4 - 5 × 10 ¹³ G) do not display any burst, while at least one case of "low-B" NSs (SGR 0418+5729) does, if the magnetic field is their driving force?